swsusp: clean up shrink_all_zones()

Move local variables to innermost possible scopes and use local
variables to cache calculations/reads done more than once.

No change in functionality (intended).

Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Len Brown <lenb@kernel.org>
Cc: Greg KH <gregkh@suse.de>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/mm/vmscan.c b/mm/vmscan.c
index 550e8695070deab28cd770847238e57697cb5c46..6177e3bcd66bdc7b8fc74cb583d47bb89c4940ef 100644 (file)
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -2057,31 +2057,31 @@ static unsigned long shrink_all_zones(unsigned long nr_pages, int prio,
                                      int pass, struct scan_control *sc)
 {
        struct zone *zone;
-       unsigned long nr_to_scan, ret = 0;
-       enum lru_list l;
+       unsigned long ret = 0;
 
        for_each_zone(zone) {
+               enum lru_list l;
 
                if (!populated_zone(zone))
                        continue;
-
                if (zone_is_all_unreclaimable(zone) && prio != DEF_PRIORITY)
                        continue;
 
                for_each_evictable_lru(l) {
+                       enum zone_stat_item ls = NR_LRU_BASE + l;
+                       unsigned long lru_pages = zone_page_state(zone, ls);
+
                        /* For pass = 0, we don't shrink the active list */
-                       if (pass == 0 &&
-                               (l == LRU_ACTIVE || l == LRU_ACTIVE_FILE))
+                       if (pass == 0 && (l == LRU_ACTIVE_ANON ||
+                                               l == LRU_ACTIVE_FILE))
                                continue;
 
-                       zone->lru[l].nr_scan +=
-                               (zone_page_state(zone, NR_LRU_BASE + l)
-                                                               >> prio) + 1;
+                       zone->lru[l].nr_scan += (lru_pages >> prio) + 1;
                        if (zone->lru[l].nr_scan >= nr_pages || pass > 3) {
+                               unsigned long nr_to_scan;
+
                                zone->lru[l].nr_scan = 0;
-                               nr_to_scan = min(nr_pages,
-                                       zone_page_state(zone,
-                                                       NR_LRU_BASE + l));
+                               nr_to_scan = min(nr_pages, lru_pages);
                                ret += shrink_list(l, nr_to_scan, zone,
                                                                sc, prio);
                                if (ret >= nr_pages)
@@ -2089,7 +2089,6 @@ static unsigned long shrink_all_zones(unsigned long nr_pages, int prio,
                        }
                }
        }
-
        return ret;
 }